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.TH MESG 1 "Oct 31, 1997"
.SH NAME
mesg \- permit or deny messages
.SH SYNOPSIS
.LP
.nf
\fBmesg\fR [\fB-n\fR | \fB-y\fR | n | y]
.fi

.SH DESCRIPTION
.sp
.LP
The \fBmesg\fR utility will control whether other users are allowed to send
messages via \fBwrite\fR(1), \fBtalk\fR(1), or other utilities to a terminal
device. The terminal device affected is determined by searching for the first
terminal in the sequence of devices associated with standard input, standard
output, and standard error, respectively. With no arguments, \fBmesg\fR reports
the current state without changing it. Processes with appropriate privileges
may be able to send messages to the terminal independent of the current state.
.SH OPTIONS
.sp
.LP
The following options are supported:
.sp
.ne 2
.na
\fB\fB-n\fR|\fBn\fR \fR
.ad
.RS 9n
Denies permission to other users to send message to the terminal. See
\fBwrite\fR(1).
.RE

.sp
.ne 2
.na
\fB\fB-y\fR|\fBy\fR \fR
.ad
.RS 9n
Grants permission to other users to send messages to the terminal.
.RE

.SH ENVIRONMENT VARIABLES
.sp
.LP
See \fBenviron\fR(7) for descriptions of the following environment variables
that affect the execution of \fBmesg\fR: \fBLANG\fR, \fBLC_ALL\fR,
\fBLC_CTYPE\fR, \fBLC_MESSAGES\fR, and \fBNLSPATH\fR.
.SH EXIT STATUS
.sp
.LP
The following exit values are returned:
.sp
.ne 2
.na
\fB\fB0\fR \fR
.ad
.RS 6n
if messages are receivable.
.RE

.sp
.ne 2
.na
\fB\fB1\fR \fR
.ad
.RS 6n
if messages are not receivable.
.RE

.sp
.ne 2
.na
\fB\fB2\fR \fR
.ad
.RS 6n
on error.
.RE

.SH FILES
.sp
.ne 2
.na
\fB\fB/dev/tty*\fR \fR
.ad
.RS 15n
terminal devices
.RE

.sp
.ne 2
.na
\fB\fB/dev/pts/*\fR \fR
.ad
.RS 15n
terminal devices
.RE

.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(7) for descriptions of the following attributes:
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
Interface Stability	Standard
.TE

.SH SEE ALSO
.sp
.LP
.BR talk (1),
.BR write (1),
.BR attributes (7),
.BR environ (7),
.BR standards (7)
